/*
 * This file is part of "JTA - Telnet/SSH for the JAVA(tm) platform".
 *
 * (c) Matthias L. Jugel, Marcus MeiÃŸner 1996-2005. All Rights Reserved.
 *
 * Please visit http://javatelnet.org/ for updates and contact.
 *
 * --LICENSE NOTICE--
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 * --LICENSE NOTICE--
 *
 */

package TelnetClient.dependencies;

import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;
import java.net.Socket;

import java.util.Vector;
import java.util.Properties;

import java.awt.Dimension;

/**
 * The telnet wrapper is a sample class for how to use the telnet protocol
 * handler of the JTA source package. To write a program using the wrapper you
 * may use the following piece of code as an example:
 *
 * <PRE>
 * TelnetWrapper telnet = new TelnetWrapper();
 * try
 * {
 *     telnet.connect(args[0], 23);
 *     telnet.login(&quot;user&quot;, &quot;password&quot;);
 *     telnet.setPrompt(&quot;user@host&quot;);
 *     telnet.waitfor(&quot;Terminal type?&quot;);
 *     telnet.send(&quot;dumb&quot;);
 *     System.out.println(telnet.send(&quot;ls -l&quot;));
 * }
 * catch (java.io.IOException e)
 * {
 *     e.printStackTrace();
 * }
 * </PRE>
 *
 * Please keep in mind that the password is visible for anyone who can download
 * the class file. So use this only for public accounts or if you are absolutely
 * sure nobody can see the file.
 * <P>
 * <B>Maintainer:</B> Matthias L. Jugel
 *
 * @version $Id: TelnetWrapper.java 499 2005-09-29 08:24:54Z leo $
 * @author Matthias L. Jugel, Marcus Meiï¿½ner
 */
public class TelnetWrapper extends Wrapper
{
    protected TelnetProtocolHandler handler;

    /** debugging level */
    private final static int debug = 0;

    public TelnetWrapper()
    {
	handler = new TelnetProtocolHandler()
	{
	    /** get the current terminal type */
	    public String getTerminalType()
	    {
		return "vt320";
	    }

	    /** get the current window size */
	    public Dimension getWindowSize()
	    {
		return new Dimension(80, 25);
	    }

	    /** notify about local echo */
	    public void setLocalEcho(boolean echo)
	    {
		/* EMPTY */
	    }

	    /** write data to our back end */
	    public void write(byte[] b) throws IOException
	    {
		out.write(b);
	    }

	    /** sent on IAC EOR (prompt terminator for remote access systems). */
	    public void notifyEndOfRecord()
	    {
	    }
	};
    }

    public TelnetProtocolHandler getHandler()
    {
	return handler;
    }

    public void connect(String host, int port) throws IOException
    {
	super.connect(host, port);
	handler.reset();
    }

    /**
     * Send a command to the remote host. A newline is appended and if a prompt
     * is set it will return the resulting data until the prompt is encountered.
     *
     * @param cmd
     *            the command
     * @return output of the command or null if no prompt is set
     */
    public String send(String cmd) throws IOException
    {
	byte arr[];
	arr = (cmd + "\n").getBytes();
	handler.transpose(arr);
	if (getPrompt() != null)
	    return waitfor(getPrompt());
	return null;
    }

    /**
     * Read data from the socket and use telnet negotiation before returning the
     * data read.
     *
     * @param b
     *            the input buffer to read in
     * @return the amount of bytes read
     */
    public int read(byte[] b) throws IOException
    {
	/* process all already read bytes */
	int n;

	do
	{
	    n = handler.negotiate(b);
	    if (n > 0)
		return n;
	}
	while (n == 0);

	while (n <= 0)
	{
	    do
	    {
		n = handler.negotiate(b);
		if (n > 0)
		    return n;
	    }
	    while (n == 0);
	    n = in.read(b);
	    if (n < 0)
		return n;
	    handler.inputfeed(b, n);
	    n = handler.negotiate(b);
	}
	return n;
    }
}
